Self-Configure:
Make clear there is two Personal Time Zone in the backend (User Time Zone and System Time Zone).
Key Point:
Make clear to the time convert during backend and frontend.
(1)In DB, it’s CET time.
(3)In our program, we can’t transport User Time Zone out to UI directly, we should convert User Time Zone to UTC and update it_ausg. (it’s better for UI to convert UTC to your browser time)